Incandescent-electric-lamp cut-out



(No Model.)

W. F. SMITH. v INGANDESGENT ELECTRIC LAMP GUT-OUT. v No. 525,293.Patented Aug. 28, 1894.

' in lilililha Nrrs STATES PATENT OFFICE.

WALTER F. SMITH, OF PHILADELPHIA, PENNSYLVANIA, ASSIGNOR TO THE HEISLERELECTRIC COMPANY, OF GLOUCESTER CITY, NEW JERSEY.

INCANDESCENT-ELECTRlC-LAMP CUT-OUT.

SPECIFICATION forming part of Letters Patent No. 525,293, dated August28, 1894. Application filed August 28, 1889. Serial No. 321,724. (Nomodel.)

.To all whom it may concern:

Be it known that I, WALTER F. SMITH, a citizen of the United States,residing at Phila-' delphia, in the county of Philadelphia and State ofPennsylvania, have invented certain new and useful Improvements inIncandescent Electric Lamps, of which the following is a specification.

My invention relates to an improved cutout device for an incandescentelectric lamp arranged preferably for use in series with one anotherwith a current of high electro-motive force.

The principal objects of my invention are: first, to provide a sensitivecut-out simple, durable and positive in action; second, to provide acut-out which in the event of the filaments of one or more of the lampsdisposed in series being broken or otherwise destroyed will shortcircuit the electric current and automatically cut the lamp to which itis attached out of the dynamo or generator circuit; and third, toprovide a device arranged so that the parts thereof may be readilyreadjusted without interrupting the dynamo or generator circuit when thedefect in the lamp Cvlvhiich caused the cut-out to operate, is reme- Myinvention consists in shunting the electrlc current traversing thedynamo or generator circuit in which the lamp is included and causingone portion of the current to pass through the filament of p the lampand the other through the shunt circuit and with a substance or materialof high electrical resistance readily melting or softening interposed insaid shunt circuit with a pin in contact therewith and an actuatedlever, whereby the lamp is short circuited by the melting or softeningof said substance or material.

My invention further consists in providing an electric lamp with acombined switch and cut-out, whereby the filament of the lamp may bemechanically included in or excluded from the dynamo or generatorcircuit and when the lamp is included in said circuit, with the currentshunted, that is, one part passing through the filament of the lamp andthe other through the shunt circuit in which is included a material orsubstance of high electrical resistance susceptible of being readilymelted or softened and means to automatically short circuit the dynamoor gonerator circuit in the event of said filament being broken.

The nature and characteristic features of my invention will be morefully understood taken in connection with the accompanying drawingsforming part hereof and in which- Figure 1, is a view partly inelevation and partly in section of an incandescent lamp and its holdershowing my improved cut-out device in application. Fig. 2, is a similarview of a lamp holder with my improved automatic-cut-out, 'shuntcircuit, the material of high electrical resistance interposed in saidshunt circuit and the means for short circuiting the dynamo or generatorcircuit; and Fig. 3, is a similar view of a combined switch and cut-outdevice, whereby the filament of the lamp may be mechanically included inor excluded from the dynamo or generator circuit.

Referring to the drawings and more particularly to Figs. 1 and 2, 0c isthe base plate of the holder composed of insulating material andprovided with an aperture 00 in the center thereof. The vertical metalsupport A, is secured to the base plate m, in any preferred manner andis provided with a binding screw or other terminal device a and with abifurcated shoulder or lug 0. having a bearing a formed therein. Thevertical support A is secured to the base plate 0c,in any preferredmanner and is provided near the upper extremity thereof with a similarbinding screw or other terminal device a and with an aperture a. Thefilament y of suitable material is secured to the vertical supports Aand A, in any preferred manner and held within a sealed bulb I. A bellcrank lever E, is pivotally connected with the bifurcated lug orshoulder a and is provided with a finger e, and a wing e A spring F,

is interposed between the bell crank lever E and the base ofthe'vertical support A, which holds the finger e, normally in contactwith the upper part of the vertical support A.

C is a threaded metal plug fitted into the aperture a of the support A,and having a tapped chamber 0 and an insulating thumbpiece D, mounted onor secured to the shank c of said-plug by means of a pin c G is a thindisk, pellet or substance of high electrical resistance but ofsubstantial rigidity or hardness when cold, yet, nevertheless, capableof being melted or softened at a low temperature and which is fitted orloosely mounted in the chamber 0 of the plug G. The disk, pelletorsubstance G, may be made of rubber or graphite or any other preferredmaterial.

G is a plug of suitable insulating material secured into the threadedmetal plug O, and this plug serves to retain the disk, pellet orsubstance G in the chamber 0 of the said plug 0.

It is a metallic pin, bar or device titted loosely into and extendingthrough the insulating plug G, one end of which is in contact with thewing c of the bell crank lever E, and the opposite end in contact withthe disk, pellet or substance G, mounted in the chamber 0 of the metalplug 0.

K and K are wires or other conductors attached to the terminals a anda", of the supports A and A, respectively and lead to the dynamo orother source of electric energy.

I is a metal threaded thimble secured to the base plate a, and by whichthe lamp socket or holder is secured to the electrolier or otherfixture. The wires K and K extend through the aperture a" in the baseplate a: and through the thimble I.

I is the housing of the lamp within which the various parts thereof areconfined and this housing is insulated from the thimble I, by means of agasket W.

l is a support for a globe or shade l illus trated in dotted lines and Iis the neck of a glass bulb in dotted lines the lower portion thereofbeing shown broken away.

x and 00 are insulating disks which support the vertical conductors Aand A, and also the housing I.

M and M are spring actuated clamps of the usual or any preferredconstruction which serve to retain the glass bulb in position and N is aswitch of suitable construction adapted to short circuit the filamentand extinguish the lamp.

In Fig. 3 is shown my invention in another form in which the switch andcut-out are combined for operation in the manner to be described.

D is the insulating plug secured onto a threaded shank C ofgood-conducting material and extending through an opening a in thevertical support A. Into this hollow shank O of the plug D, isintroduced a smooth surfaced plug G, of any preferred insulatingmaterial and through which plug is inserted a horizontal pin or bar H,of good conducting material. In the rear of the hollow threaded shank Ois fitted or packed a disk, pellet or substance of high electricalresistance susceptible of being melted ata low temperature.

The wing e of the bell-crank lever l is normally held in contact withthe head of the movable pin II, by the action of the springF, until theelectric current is sufficiently llltense to melt or soften thedislnpelletor substance G, when the pin If is automatically actuatedcausing the linger e of said bellerank lever E, to contact with theupper part of the support or conductor A, and thereby causing thetilament of the lamp to be cut out of the dynamo or generator circuit.

N is a spring of any preferred construction secured or attached to thevertical support A, and the free extremity of this spring is normally incontact with the smooth surfaced plug G, of insulating material mountedin the hollow threaded shank C of the insulating plug D. This spring N,normallyin contact with the smooth surfaced plug G, performs thefunctions, when the thumb piece I) is actuated, of a switch to shortcircuit the filament as well as extinguish the lamp. The spring N incontact with the smooth surfaced plug G, as shown in Fig. permits of thecurrent passing from the dynamo or generator through the wire K to thebinding post a", thence through the vertical conductor A and thefilament 3/ to the support or conductor A and the binding post a andthen by the wire K to the next lamp in series or to the source ofelectric energy. The several parts of the lamp are in other respectssubstz'tntially the same as the one described in Figs. 1. and 2, thereal difference being that in Fig. 3 the switch plug and its parts arecombined with the cut-out and operated by hand to cause the same toperform its respective functions while in Figs. 1 and 2, the switch plugN, for extinguishing the lamp is separate and dis tinct from the cut-outdevice.

The mode of operation of my improved cutout device is as followsa-Toadjust the device, the plug C carrying the movable pin or bar II and thedisk, pellet or substance G, is screwed into the surface surrounding theopening a, of the vertical arm A, until the pin H, normally in contactwith the wing 6 overcomes the resistance of the spring F, and raises thefinger c, therebybreaking the contact between the finger and thevertical. support A. The lamp is then interposed in the dynamo orgenerator circuit in the usual or in any other preferred manner and theelectric current entering the lamp is shunted. One part of the currentof the generator circuit passing through the vertical supports A,filament 'y and the vertical support A,to the source of electric energyand the other part of the current passing through the bell crank leverE, the pin II, the disk, pellet or substance Gr, to the source ofelectric energy. In the event of the filament being broken or otherwiseinjured the shunt current will greatly increase in intensity and thedisk, pellet or substance G, by reason of its high electrical resistancewill become heated, melted or softened so that the spring F, will causethe pin H, to sink into said disk and the finger e to come in contactwith the vertical support A, whereby the current is short circuitedthrough the bell crank lever E and the lamp cut-out of the dynamo orgenerator circuit. To readjust the cut-out device when the broken orotherwise injured filament has been replaced by a new one, the plug 0 isremoved and a new disk, pellet or substance G, inserted and the plugreplaced as in the first instance. By unscrewing the plug D, asillustrated in Fig. 3, the dynamo or generator current entering the lampby the wire K is shunted either through the binding post a support A,switch N, metal plug 0, support A, binding post M, to the wire K, orshunted through the binding post a support A, bell crank lever E,support A, and binding post a to the wire K, or the dynamo or generatorcurrent by the above described arrangement of parts divides and passesthrough both of the said several devices so that in any event thecurrent will be shunted or the lamp short circuited by the mere rotationby hand of the thumb piece D, to extinguish the lamp. The automaticcut-out mechanism illustrated in Fig. 3 is arranged for operation in asimilar manner to that hereinbefore described in connection with Figs. 1and 2.

Having thus described the nature and objects of my invention,what Iclaim as new, and desire to secure by Letters Patent, is

1. In an incandescent electriclamp, ashunt circuit, a substance of highelectrical resistance readily melting or softening interposed in saidcircuit, a movable pin contacting with said substance and a lever heldin contact with said pin and short circuiting the lamp by the meltingorsofteningof said substance, substantially as and for the purposesdescribed.

2. The combination with an electric lamp, of a substance readily meltingor softened interposed in a shunt circuit and a spring actuated levercontacting with a pin which normally engages with said substance,substantially as and for the purposes described.

3. In an electric lamp,the combination of a metallic plug, a disk ofhigh resistance melting or softening at a low temperature held in saidplug, a pin mounted in an insulating plug and a spring actuated shortcircuiting lever normally in contact with said pin, substantially as andfor the purposes set forth.

at. In an electric lamp, the combination with vertical supports, aspring actuated short circuiting device pivotally connected with one ofsaid supports, a plug secured into the other support, a movable pin, apellet melting at a low temperature interposed between said pin andplug, substantially as and for the purposes set forth.

5. A cut-out device for an electric lamp consisting of a plug ofconducting material, a pellet of poor electrical conductivity andmelting at a low temperature supported in said plug, an insulating plugattached to said plug, a movable pin held in said insulated plug, aspring in contact with said insulated plug and a spring actuatedbell-crank lever in contact with said pin,substantially as and for thepurposes set forth.

6. In an electric lamp, the combination of a spring actuated bellcrank-lever, a metal plug with an insulated thumb-piece, an insulatingplug secured to said metal plug,-a pellet of high electrical resistancemelting or softening at a low temperature held in said metal plug, a pinmounted in said insulated plug and in contact with said pellet andlever, substantially as and for the purposes set forth.

7. In a cut-out device for an electric lamp, a metal plug provided witha disk of high electrical resistance but melting or softening at a lowtemperature interposed in a shunt circuit, an insulating plug mounted insaid metal plug, a spring in engagement with the latter plug and a shortcircuiting lever in contact with said disk, substantially as and for thepurposes set forth.

In witness whereof I have hereunto set my signature in the presence oftwo subscribing Witnesses.

WALTER F. SMITH.

Witnesses:

ALEX. O. HUMPHREYS, CHARLES E. SMALL.

